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41.
Lymphosarcoma in a six year old male Doberman pinscher was accompanied by hypercalcemia, generalized osteolysis and renal calcification. Tumor involvement of bone marrow was extensive. The possible pathogenesis of hypercalcemia was thought to be the result of a locally active bone-resorbing factor secreted by the tumor cells.  相似文献   
42.
Urethral obstruction in a male llama   总被引:1,自引:0,他引:1  
An 8-year-old sexually intact male llama was euthanatized because of obstruction of the penile portion of the urethra and rupture of the urinary bladder. Clinical signs of obstruction included anorexia, lethargy, teeth grinding, straining to defecate, inability to urinate, and tense abdomen. Laboratory findings included anemia, leukocytosis with left shift, high serum urea nitrogen, creatinine, and phosphorus concentrations, and low serum chloride concentration. Necropsy revealed ruptured urinary bladder and acute fibrinous peritonitis. A firm, gray, nonmineralized urethral plug occluded the penile portion of the urethra for a distance of 14 cm in the midpenile region, distal to the sigmoid flexure of the penis. The urinary bladder mucosa and the urethra had microscopic evidence of chronic inflammation. Escherichia coli, Klebsiella sp, and alpha-streptococci were isolated from the urethral plug.  相似文献   
43.
OBJECTIVE: To objectively evaluate the effect of transecting the tendon of the biceps brachii muscle (BBT), tendon of the infraspinatus muscle (IFS), or medial glenohumeral ligament (MGHL) on shoulder joint stability in canine cadavers. SAMPLE POPULATION: 81 forelimbs from mature dogs. PROCEDURE: Cadaver forelimbs were placed in a testing frame and axially preloaded with 4 kg of weight. Shoulder joint stability was tested in neutral joint position, flexion, and extension before and after transection of the BBT (n = 37), IFS (37), or MGHL (7). Humeral translation relative to the glenoid was induced by applying a 3-kg load in each of 3 directions (cranial, lateral, and medial) and quantitatively measured by use of an electromagnetic motion tracking system. Peak translational data were compared in each joint position before and after transection of the BBT, IFS, or MGHL. RESULTS: When tested in neutral position, the cranial, lateral, and medial translation of the humerus was significantly increased after BBT transection. In the flexed position, translation of the humerus in the cranial and lateral directions was significantly increased after BBT transection. In the extended position, the medial translation of the humerus was significantly increased after BBT transection. Complete medial luxation of all humeral heads occurred following transection of the MGHL. CONCLUSIONS AND CLINICAL RELEVANCE: The BBT contributes to passive shoulder joint stability in dogs, particularly in the neutral and flexed positions. It also provides medial stability during shoulder joint extension. Complete luxation of the joint occurs when the MGHL is transected.  相似文献   
44.
A purified protein derivative-live preparation of Brucella abortus strain 45/20 was tested for immunogenic properties either alone, after lipid conjugation, or in association with defined adjuvants. The adjuvants were trehalose dimycolate (cord factor), isolated from wax D of mycobacteria and murmyl dipeptide (N-acetyl-muramyl-L-alamyl-D-isoglutamine), a synthetic glycopeptide analog of peptidoglycan subunits found in many bacterial cell walls and wax D of mycobacteria. Guinea pigs were intradermally inoculated with a single injection of the vaccine preparations eight weeks before intramuscular challenge with B. abortus, strain 2308. None of the purified protein derivative-like preparations were as effective in the prevention of splenic infections with B. abortus as were killed whole cells of strain 45/20 in Freund's complete adjuvant. Whole cells in Freund's complete adjuvant were able to reduce mean colony counts by 97% (P = 0.02), while purified protein derivative-like vaccines were able to reduce mean colony counts by only 32 to 61% as compared to control animals. Results suggest that purified protein derivative-like preparations have limited immunogenic properties under present test conditions.  相似文献   
45.
The field of veterinary radiation therapy (RT) has gained substantial momentum in recent decades with significant advances in conformal treatment planning, image‐guided radiation therapy (IGRT), and intensity‐modulated (IMRT) techniques. At the root of these advancements lie improvements in tumor imaging, image alignment (registration), target volume delineation, and identification of critical structures. Image registration has been widely used to combine information from multimodality images such as computerized tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) to improve the accuracy of radiation delivery and reliably identify tumor‐bearing areas. Many different techniques have been applied in image registration. This review provides an overview of medical image registration in RT and its applications in veterinary oncology. A summary of the most commonly used approaches in human and veterinary medicine is presented along with their current use in IGRT and adaptive radiation therapy (ART). It is important to realize that registration does not guarantee that target volumes, such as the gross tumor volume (GTV), are correctly identified on the image being registered, as limitations unique to registration algorithms exist. Research involving novel registration frameworks for automatic segmentation of tumor volumes is ongoing and comparative oncology programs offer a unique opportunity to test the efficacy of proposed algorithms.  相似文献   
46.
Preparations derived from plants were the original therapeutic interventions used by man to control diseases (including parasites), both within humans and livestock. Development of herbal products depended upon local botanical flora with the result that different remedies tended to develop in different parts of the world. Nevertheless, in some instances, the same or related plants were used over wide geographic regions, which also was the result of communication and/or the importation of plant material of high repute. Thus, the Nordic countries have an ancient, rich and diverse history of plant derived anthelmintic medications for human and animal use. Although some of the more commonly used herbal de-wormers were derived from imported plants, or their products, many are from endemic plants or those that thrive in the Scandinavian environment. With the advent of the modern chemotherapeutic era, and the discovery, development and marketing of a seemingly unlimited variety of highly efficacious, safe synthetic chemicals with very wide spectra of activities, herbal remedies virtually disappeared from the consciousness--at least in the Western world. This attitude is now rapidly changing. There is a widespread resurgence in natural product medication, driven by major threats posed by multi-resistant pest, or disease, organisms and the diminishing public perceptions that synthetic chemicals are the panacea to health and disease control. This review attempts to provide a comprehensive account of the depth of historical Nordic information available on herbal de-wormers, with emphasis on livestock and to provide some insights on potentially rewarding areas of "re-discovery" and scientific evaluation in this field.  相似文献   
47.
Foot-and-mouth disease virus (FMDV) is the causative agent of a highly contagious acute vesicular disease affecting cloven-hoofed animals, including cattle, sheep and pigs. The current vaccine induces a rapid humoral response, but the duration of the protective antibody response is variable, possibly associated with a variable specific CD4+ T cell response. We investigated the use of heat shock protein 70 (Hsp70) as a molecular chaperone to target viral antigen to the Major Histocompatibility Complex (MHC) class II pathway of antigen presenting cells and generate enhanced MHC II-restricted CD4+ T cell responses in cattle. Monocytes and CD4+ T cells from FMDV vaccinated cattle were stimulated in vitro with complexes of Hsp70 and FMDV peptide, or peptide alone. Hsp70 was found to consistently improve the presentation of a 25-mer FMDV peptide to CD4+ T cells, as measured by T cell proliferation. Complex formation was required for the enhanced effects and Hsp70 alone did not stimulate proliferation. This study provides further evidence that Hsp70:peptide complexes can enhance antigen-specific CD4+ T cell responses in vitro for an important pathogen of livestock.  相似文献   
48.
The sperm‐mediated gene transfer method is applicable to transgenesis in many species that use spermatozoa for reproduction recently, which has been shown various results. In the current study, we show that transgenic porcine embryos can be efficiently produced by employing a simple transfection method that uses magnetic nanoparticles (MNPs). The complexes formed between plasmid DNA and MNPs were bounded on ejaculated boar spermatozoa at a higher efficiency compared to methods using DNA alone or lipofection. Using confocal microscopy, rhodamine fluorophore‐labelled MNPs were detected on external surfaces of the spermatozoa membrane, which were bounded on zona pellucida of in vitro maturated oocyte during in vitro fertilization. Electron microscopy revealed that clusters of MNPs were detected in inside of plasma membrane and nucleus of the spermatozoa head. Additionally, we found that magnetofected boar spermatozoa could be fertilized with oocytes in vitro and that the resulting gene of green fluorescent protein was detected in fertilized eggs by genomic PCR analysis. Taken together, these results suggest that MNPs can be used to efficiently introduce a transgene into embryo via spermatozoa.  相似文献   
49.
The aim of this study was to determine which cells are the source of production and target for leukotriene (LTs) action within the bovine ovary. Luteal (CL, days 14–16 of the oestrous cycle), steroidogenic cells (LSC) and endothelial cells (LEC) of the bovine corpus luteum (CL), and granulosa cells (GC) were isolated enzymatically, cultured in a monolayer and incubated with LTC4, LTB4, Azelastine (an antagonist of LTC4) or Dapsone (an antagonist of LTB4). Then cells were collected for determination of mRNA expression for LT receptors (LTRs) and 5‐lipoxygenase (5‐LO) by real time RT‐PCR, and media were collected for determination of prostaglandin (PG)E2, F, progesterone (P4; LSC only), endothelin‐1 (ET‐1; LEC only) and 17‐β oestradiol (E2; GC only). The greatest mRNA expression for LTR‐II and 5‐LO were found in LEC, whereas LTR‐I mRNA expression did not differ among cell types. The level of PGE2 increased after LTs treatment in each type of ovarian cell, excluding LTC4 treatment in LEC. The secretion of PGF was also increased by LTs, but decreased after LTB4 treatment of LSC. In GC cultures, both LTs stimulated E2 secretion; in LEC cultures, LTB4 stimulated whereas LTC4 inhibited P4 secretion; in LEC cultures, LTC4 stimulated but LTB4 inhibited ET‐1 secretion. The results show that LTs are produced locally and are involved in PGs production/secretion in all examined cells (LSC, LEC and GC) of bovine ovary. Leukotriene treatment modulate secretion of E2, by GC, P4 by LSC and ET‐1 by LEC, which indicates that LTs are involved in regulation of ovarian secretory functions.  相似文献   
50.
Clusterin (CLU), also known as apolipoprotein J, is a widely expressed, heterodimeric, glycoprotein, important in tumourigenesis, apoptosis and immunoregulation. In humans, CLU expression has been associated with anaplastic large cell and Hodgkin's lymphoma. In this study, serum CLU levels in dogs with multicentric lymphoma (MLSA) were compared with healthy control dogs, using both western blot and enzyme‐linked immunosorbent assay (ELISA). Western blot confirmed the presence of CLU in dog sera at the predicted molecular weight and the relative levels detected correlated with the levels detected by ELISA. CLU level analysis by ELISA found treatment naïve dogs with MLSA had a significantly (P < .001) lower serum CLU level compared with healthy controls. However, there was no significant difference between MLSA dogs prior to treatment and in complete remission. The wide variation in serum CLU levels may limit its potential as a single candidate biomarker for MLSA, although any prognostic predictive value of serum CLU concentrations has yet to be assessed.  相似文献   
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